Previously, air acoustic sensors have been utilized to form arrays and provide azimuth estimates of sound sources. However, these systems require either large mechanical devices for fixed arrays or do not provide a compact deployable unit which produces accurate results.
For example, U.S. Pat. No. 4,208,738 by Lamborn relates to a deployable sonar array with interconnected transducers including a housing with electronics where the transducers are released when the housing is launched.
U.S. Pat. No. 5,027,333 to Hailing is directed to an acoustic array including a plurality of the transducing elements which are free floating.
U.S. Pat. No. 4,559,605 to Norsworthy relates to beamforming method utilizing a number of sensing elements which take up random positions where the relative positions of the elements are determined using triangulation.
Also, a device known as Smart Standoff Mine Active Countermeasures (SSMAC) beamformer utilizes mechanical deployment of a complex shaped predetermined array to employ beamforming techniques.
Consequently, a need remains for a compact, easily deployable system where transducers are randomly dispersed and a coordinate system may be formed so that accurate azimuth outputs and target class estimates are obtained from advanced beamforming techniques. The present invention eliminates physical constraints in transducer locations allowing use of larger arrays with a greater number of transducers which results in significant performance improvement.